Abstract:
The structure and evolution of the photospheric magnetic fields observed in the active region NOAA 10570
are analyzed using Kodaikanal photoheliogram and spectroheliogram data. It is attempted to evaluate the
shear angle changes by carefully observing the prominent umbrae belonging to the active region. These
changes in the orientation of the umbrae infer the rotational motion developed in the sunspot group. It is
found that the flux and shear angle changes observed in the sunspot configurations are related to triggering
of flares in the active region NOAA 10570.
